1. Field of the Invention
The present invention relates to a wire harness, a wire harness manufacturing method and a wire harness manufacturing apparatus, and more particularly, to a wire harness in which a predetermined part of electric wire is provided with a member having a function of protecting the electric wire and/or a function of bundling plural electric wires, a method for manufacturing the wire harness, and an apparatus capable of manufacturing the wire harness (wire harness manufacturing apparatus).
2. Description of the Related Art
In a vehicle such as an automobile, a wire harness to mutually connect electric devices and electronic devices is arranged. The wire harness used for such application generally has predetermined types and predetermined lengths of plural electric wires. These plural electric wires are bound (or bundled) in a predetermined form. Further, predetermined types of connectors and the like are attached to ends of the respective electric wires included in the wire harness. Then a predetermined part of the wire harness is provided with a member to bind (or bundle) an electric wire group not to unbind the respective electric wires and a member having a function of protecting the electric wire or electric wire group.
As a structure to bind (or bundle) an electric wire group and protect the electric wire(s), a structure to wrap a tape around the predetermined part of an electric wire group, a structure to accommodate the predetermined part of the electric wire group in a tube of resin material or the like (e.g., a corrugate tube), a structure to embed the predetermined part of the electric wire group in a molded resin member (insert molding), a structure to mold a member covering the outer peripheral surface of the predetermined part of the electric wire group using resin material, and the like, are used.
However, these structures may have the following problems.
When a tape is wrapped around the predetermined part of the electric wire group, in the tape-wrapped part, in comparison with the part before the wrapping (or an unwrapped part), the flexibility of the electric wire group (deformability of the electric wire group) is lowered. Accordingly, when the wire harness is arranged in a vehicle or the like, the handleability of the wire harness is lowered. This might reduce working efficiency. In addition, the appearance of the tape-wrapped part is bad.
In the structure where the predetermined part of the electric wire group is accommodated in a tube, the wire harness manufacturing apparatus and/or a manufacturing procedure is limited in accordance with structures of connectors and the like. Generally, predetermined connectors and the like are attached to the ends of the electric wires included in the wire harness. When the electric wires attached to the connectors cannot be passed through the tube (e.g., when the sizes of the connectors and the like are larger than an inner diameter of the tube), it is necessary, as a procedure of the wire harness manufacturing, to first pass the predetermined part of the electric wire group through the tube (accommodate the part in the tube), then, attach the connectors and the like to the ends of the electric wires. When an apparatus to automatically attach connectors and the like to the ends of electric wires may be used, however, when the electric wire group is accommodated in the tube, it is impossible to set the electric wires in such apparatus due to interference with the tube and/or the other electric wires in some cases. In this case, since it is impossible to automatically attach the connectors and the like to the ends of the electric wires, it is necessary to manually attach the connectors or the like. It is difficult to reduce the manufacturing cost of the wire harness.
In the structure using a tube in which a slit is formed, it is necessary to wrap a tape or the like around the outer peripheral surface of the tube to prevent falling of the electric wire or electric wire group. Since the number of process steps is increased, it is difficult to reduce the manufacturing cost. Further, the appearance of the tape-wrapped tube is bad.
Further, the tube used for the wire harness generally lacks a positioning mechanism with respect to the predetermined part of electric wire(s). Accordingly, it is necessary to wrap a tape or the like over the electric wire group and the tube to prevent shift of the tube from the predetermined position of the electric wire group. Accordingly, it is difficult to reduce the number of process steps. Further, the appearance of the wrapped tape is bad.
In the structure where the predetermined part of the electric wire or electric wire group is embedded in a molded part, a molding die (generally a die for injection molding) is required. It is necessary to prepare such molding die for parts in different lengths and diameters. Generally, since a molding die is expensive and is not very versatile, this structure using such molding die might increase the equipment cost.
In the structure to mold a resin part covering the predetermined part of the electric wire or electric wire group, a molding die corresponding to the outer diameter (outer shape) of the electric wire or electric wire group is required. For a reason similar to that in the above structure, the structure might increase the equipment cost. Further, in this structure, it is difficult to change the thickness of the molded part. That is, in some cases, in the member covering the predetermined part of the electric wire or electric wire group, it is desirable to increase the thickness of a part to have a function of protecting the electric wire or electric wire group while reducing the thickness of the other part. However, since the structure is approximately the same as a structure to mold a member to cover a core wire of an electric wire, it is difficult to change the thickness of the member.
In view of the above situation, the present invention has an object to provide a wire harness in which, even when a covering member is molded, the reduction of flexibility (especially bendability) of the part in which the covering member is molded can be prevented or suppressed, a manufacturing apparatus of the wire harness and a method for manufacturing the wire harness. Further, the present invention has another object to provide a wire harness in which the covering member is not shifted, a manufacturing apparatus of the wire harness and a method for manufacturing the wire harness. Further, the present invention has another object to provide a wire harness in which a good-appearance covering member is molded, a manufacturing apparatus of the wire harness and a method for manufacturing the wire harness. Further, the present invention has another object to provide a wire harness having an integrally-formed covering member in which the thickness is changed, a manufacturing apparatus of the wire harness and a method for manufacturing the wire harness. Further, the present invention has another object to provide a wire harness capable of reducing equipment cost and/or manufacturing cost or capable of preventing an increase in the equipment cost and/or manufacturing cost, a manufacturing apparatus of the wire harness and a method for manufacturing the wire harness.